Shell script to ping a domain until it works. Lets the user know when DNS has resolved

Interval pinger with an alert

((minutes = 720)) # Total minutes to run
((rc = 3)) # set to none 0 value 
while [[ $minutes -ne 0 && $rc -ne 0 ]] ; do
    ping -c 1 localhost                     # Try once.
    rc=$?
    if [[ $rc -eq 0 ]] ; then
        echo `say The Domain is Resolving.`
    else 
        echo 'Not Found'    
        ((minutes = minutes - 1))                  # So we don't go forever.
        sleep 60;                          # Wait 60 seconds to check again/.
    fi
done

if [[  $minutes -eq 0 ]] ; then                  # Make final determination.
 echo `say Timeout.`
fi